A typical wireless cellular network is constructed by base stations having transmit power and coverage of the same level, and may be classified as a homogeneous network. The transmit power and coverage of the same level refer to that the transmit power and the coverage are basically the same, or a difference in transmit power and a difference in coverage fall within set ranges. To further improve capacity and coverage performance, some low power stations (LPN) may be added within a deployment range of a macro base station (Macro eNB), and stations of different power constitute a heterogeneous network. The low power station may also be referred to as a micro base station. The purpose of deploying a micro base station lies in two aspects: improving coverage performance and increasing network capacity. When the micro base station is used to improve coverage performance, the micro base station may be deployed in a weak coverage area of a macro base station. When the micro base station is used to increase network capacity, the micro base station may be deployed in a traffic hotspot area. Because the traffic hotspot area may be located at a position with good signal quality near the center of the macro base station, when the micro base station is deployed at the position near the center of the macro base station, to allow the micro base station to cover as many user equipments (UE) as possible and expand the coverage of the micro base station, a cell range expansion (CRE) function is introduced.
The principle of the CRE function is not to change transmit power of the micro base station, but to configure a handover parameter, and add a configuration for a corresponding threshold, so as to make it easier to hand over the UE to the micro base station and make it more difficult to hand over the UE from the micro base station. By the foregoing operations, the coverage of the micro base station is expanded, but edge users of the micro base station are closer to the macro base station, and uplink and downlink interference between the macro base station and the micro base station is increased.
For the downlink interference from the macro base station to the micro base station, an enhanced inter-cell interference coordination (eICIC) technology is introduced. In eICIC, the macro base station sets an almost blank subframe (ABS), the micro base station schedules its edge user in the ABS, and the macro base station does not schedule a user of the macro base station in the ABS. In this way, the interference from the macro base station to the edge user of the micro base station is reduced, but a resource of the macro base station is wasted.